In case of simple seats of bench type, made in particular of wood, metal, stoneware or plastics, their seating and resting parts are usually uncomfortable as for shape and cold as for feeling. Various pads, rests and other accessories are made for improving sitting, while higher quality can be achieved, besides suitable selection of seating material, also by suitable heating of contact surface.
Known constructions include in particular design according to the patent file DE No. 3,334,744, where seating set is composed of sheet-metal layer moulded between two plastic layers. Similarly, according to the patent file DE No. 1,635,508, a heating wire is placed between two plastic layers. The design described in the patent file GB No. 1,319,168 is designated for heating of walls, while a heating wire is impregnated into a textile fabric, which is covered by plastic foil.
Disadvantages of these designs are in particular uneven distribution of temperature and complicated fabrication of a set.
Design of flat heating element, where a heating wire is woven into textile fabric, is known from the patent file DE No. 2,607,949. The disadvantage of this solution is that it is dangerous to touch due to electric current, and also heating is not even.